A New Cell-to-Cell Fast Balancing Circuit for Lithium-Ion Batteries in Electric Vehicles and Energy Storage System

In this paper a new cell-to-cell fast balancing circuit for Lithium-Ion batteries in the EVs (Electric Vehicles) and ESS (Energy Storage System) is proposed. In the proposed topology the energy in a high voltage cell is transferred directly to a low voltage cell through the operation of the dc-dc converter. Therefore it can achieve fast balancing with high efficiency by a simple control algorithm. In order to demonstrate the performance of the proposed topology, a prototype circuit was implemented and applied to a 12 Lithium-Ion battery module. It has been verified with the experiments that the balancing time of the proposed method is much shorter compared with those of other methods.